Audi A4 (2018)
2018 Audi A4
CarHunch analysed 14,358 real MOT records for the 2018 Audi A4. This breakdown of actual test outcomes — pass rates, defect profiles, mileage data — isn't published anywhere else.
The 2018 Audi A4 passes its MOT first time at 86%, comfortably above the UK average of 80%, suggesting solid overall reliability—though one in four of these cars have recorded a dangerous defect at some point, which is a genuine concern for buyers. Petrol versions edge out diesel with an 86.7% pass rate versus 84.6%, a modest but consistent difference.
At a median 40,307 miles for a six-year-old car, these A4s are running slightly below average wear, yet they're still accumulating an average of 5.3 advisories per test, indicating minor issues are common even on well-maintained examples. Check the full service history and have any prospective purchase inspected by an Audi specialist, particularly around suspension and electrical systems where advisories tend to cluster.
Petrol vs Diesel
Pass rate difference of 2.1 percentage points — worth knowing if you're choosing between the two.
What to check before buying a 2018 Audi A4
Practical pre-purchase checks for this age and model.
- 📋 Check the full MOT history. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. Enter the reg below for a full AI analysis.
- 🔍 Inspect for corrosion in person. Brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that's expensive to fix and can fail an MOT.
- 🛞 Check tyres and brakes. The most common advisory items at this age. Budget for replacement if they're near the limit — factor this into your offer price.
- ⚠️ 24% of these vehicles have had a dangerous defect recorded. Enter the reg below — the full MOT history will show exactly what was flagged and whether it was resolved.
- 📄 Run an HPI check. The MOT history won't show outstanding finance, insurance write-offs, or stolen status — an HPI check will.
Before you buy a Audi A4
MOT history is one piece of the puzzle. These checks can reveal what CarHunch can't.
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Pass Rate by Fuel Type
| Fuel type | Vehicles | Pass rate | Avg failures |
|---|---|---|---|
| Petrol (68%) | 9,835 | 86.7% | 0.72 |
| Diesel (31%) | 4,521 | 84.6% | 0.74 |
| Hybrid Electric (Clean) (0%) | 1 | 100% | 0 |
| Other (0%) | 1 | 100% | 0 |
Mileage Distribution
Most 2018 Audi A4 vehicles sit in the blue band. If the car you're looking at is outside it, it's either unusually low or high mileage for its age.
Half of all 2018 Audi A4 vehicles fall between 31,574 and 50,597 miles.
2018 Audi A4 — Still on the Road
Strong survival — 12,875 vehicles still getting MOTs in 2025, 95% of the peak.
Based on vehicles from this manufacture year that had at least one MOT test in each calendar year. Data from 2020–2025.
MOT History Averages
Most Common MOT Issues — 2018 Audi A4
Based on actual MOT test records for this model. Percentage shows how often each item appears across all vehicles in this cohort.
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43.6%
Nearside Front Tyre worn close to legal limit/worn on edge
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43.1%
Offside Front Tyre worn close to legal limit/worn on edge
-
32.1%
Rear Brake pad(s) wearing thin
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25.6%
Nearside Rear Tyre worn close to legal limit/worn on edge
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23.7%
Front Brake pad(s) wearing thin
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23.4%
Offside Rear Tyre worn close to legal limit/worn on edge
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15.1%
Nearside Rear Child Seat fitted not allowing full inspection of adult belt ()
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13.5%
Offside Rear Tyre slightly damaged/cracking or perishing
Data covers a 3-year window centred on 2018. Counts include advisories and failures.
Found a specific Audi A4?
Enter the reg to see its individual MOT history, AI Hunches, and how it compares to this cohort.